Need More Research on Environmental Chemical Exposure

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(By Dr. David Suzuki) Most of us are pretty strict about what we put in our bodies. Some people eat only organic meats and produce. Others are vegetarians. Many people don't use harsh chemicals in their homes or pesticides in their gardens because they don't relish being exposed to potentially hazardous substances. Unfortunately, in many cases we aren't given a choice. Whether we like it or not, the blood of every human being on the planet contains trace elements of industrial chemicals - most of which weren't even invented a century ago.

Most of us are pretty strict about what we put in our bodies. Some people eat only organic meats and produce. Others are vegetarians. Many people don't use harsh chemicals in their homes or pesticides in their gardens because they don't relish being exposed to potentially hazardous substances.


Unfortunately, in many cases we aren't given a choice.


Whether we like it or not, the blood of every human being on the planet contains trace elements of industrial chemicals - most of which weren't even invented a century ago. Some of these chemicals have been well studied and we are aware of the risks associated with them. But for many others, we simply don't know what the long-term effects are or at what levels they become a hazard.


We are exposed to these chemicals every day in a variety of ways. Some are airborne and we breathe them into our lungs. Others are found in our water supplies. Some are in our soils. And others are in the food we eat and the products we buy. Most of them are byproducts of the way goods are made or how they break down after they are produced.


A recent report from the U.S. Centre for Disease Control and Prevention (CDC) looked at human exposure to these chemicals. Using data from urine and blood samples, the report examined the amounts of 148 chemicals in the U.S. population from 2001 to 2002. The goal is to track exposure to these chemicals over time and try to determine risk levels for various segments of the population.


As the report points out, just because these chemicals are in our blood does not necessarily mean they are harmful to us. However, many of the chemicals, such as lead and mercury, are known to be dangerous, while for many others, there is just insufficient information. The fact that they find their way into our bodies at all is cause for some concern.


Fortunately, there is some good news in the report. In the early 1990s, 4.4 per cent of children tested had elevated levels of lead (a neurotoxin) in their blood. By 2002, that number had dropped to 1.6 per cent. Levels of certain pesticides, like aldrin and dieldrin, have also dropped to low or undetectable levels.


These results show how effective strong environmental legislation can be. Efforts to reduce lead in our environment - for example, by banning it as a gasoline additive - took many years to achieve because of industry opposition, but have been very successful in reducing our exposure to this toxin. Pesticides like aldrin and dieldrin have also been phased out and, as a result, are also disappearing from our blood.


But there are new chemicals coming on the market practically every day. The CDC found widespread exposure to pyrethroid pesticides, for example, which have been poorly studied in terms of human health, and phthalates, which are common in plastics and have been linked to reproductive abnormalities.


One of the groups most vulnerable to exposure to industrial chemicals is children. Children are not just small adults. Their bodies and brains are developing rapidly. They metabolize things differently. They play on grass and in the dirt. They chew on things and get into everything.


In the United States, there's a great new initiative called the National Children's Study, which will examine the effect of environmental influences on children from before birth to the age of 21. The study will follow 100,000 children in the U.S. as they grow to find out how chemical exposure, genetics, physical surroundings and a number of other factors affect development. Right now, there are no Canadian children planned for the study, but it is not too late for the federal government to fund a Canadian component and take part in this vital research.


We all deserve a choice over what we put into our bodies An ever-expanding list of pervasive chemicals in our environment takes away that choice. We need to take it back.


Take the Nature Challenge and learn more at www.davidsuzuki.org.